U.S. patent application number 14/706987 was filed with the patent office on 2016-03-03 for transistor and manufacturing method thereof.
The applicant listed for this patent is E Ink Holdings Inc.. Invention is credited to Chia-Wei Chou, Cheng-Hang Hsu, Chuang-Chuang Tsai, Hsiao-Wen Zan.
Application Number | 20160064499 14/706987 |
Document ID | / |
Family ID | 55403470 |
Filed Date | 2016-03-03 |
United States Patent
Application |
20160064499 |
Kind Code |
A1 |
Zan; Hsiao-Wen ; et
al. |
March 3, 2016 |
TRANSISTOR AND MANUFACTURING METHOD THEREOF
Abstract
A transistor including a substrate, a gate layer, a first
insulating layer, an active layer, a source and a drain is
provided. The gate layer is disposed on the first insulating layer,
and has a plurality of first through holes. The first insulating
layer covers the gate layer and a part of the substrate exposed by
the first through holes, and forms a plurality of recesses
respectively corresponding to the first through holes. The active
layer is disposed on the first insulating layer, and has a
plurality of second through holes. The second through holes
communicate with the recesses, respectively. The source is disposed
on a part of the active layer. The drain is disposed on another
part of the active layer. A manufacturing method of the transistor
is also provided.
Inventors: |
Zan; Hsiao-Wen; (Hsinchu,
TW) ; Tsai; Chuang-Chuang; (Hsinchu, TW) ;
Chou; Chia-Wei; (Hsinchu, TW) ; Hsu; Cheng-Hang;
(Hsinchu, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
E Ink Holdings Inc. |
Hsinchu |
|
TW |
|
|
Family ID: |
55403470 |
Appl. No.: |
14/706987 |
Filed: |
May 8, 2015 |
Current U.S.
Class: |
257/40 ; 257/43;
438/104; 438/99 |
Current CPC
Class: |
H01L 21/28026 20130101;
H01L 21/28158 20130101; H01L 29/7869 20130101; H01L 29/1037
20130101; H01L 29/78696 20130101; H01L 29/78648 20130101; H01L
21/0272 20130101; H01L 21/3083 20130101; H01L 29/66969 20130101;
H01L 29/0692 20130101; H01L 29/4238 20130101; H01L 29/42384
20130101; H01L 29/42368 20130101; H01L 29/78645 20130101; H01L
51/0508 20130101; H01L 21/31144 20130101 |
International
Class: |
H01L 29/423 20060101
H01L029/423; H01L 29/06 20060101 H01L029/06; H01L 29/10 20060101
H01L029/10; H01L 21/28 20060101 H01L021/28; H01L 21/308 20060101
H01L021/308; H01L 29/66 20060101 H01L029/66; H01L 29/78 20060101
H01L029/78 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 26, 2014 |
TW |
103129352 |
Claims
1. A transistor, comprising: a substrate; a gate layer, disposed on
the substrate, and having a plurality of first through holes; a
first insulating layer, covering the gate layer and a part of the
substrate exposed by the first through holes, and forming a
plurality of recesses respectively corresponding to the first
through holes; an active layer, disposed on the first insulating
layer, and having a plurality of second through holes, wherein the
second through holes communicate with the recesses, respectively; a
source, disposed on a part of the active layer; and a drain,
disposed on another part of the active layer.
2. The transistor of claim 1, further comprising an insulating
material layer, disposed on the substrate, and located between the
gate layer and the substrate, wherein the insulating material layer
has a plurality of pores communicating with the first through
holes, respectively.
3. The transistor of claim 2, wherein a material of the insulating
material layer comprises an organic dielectric material.
4. The transistor of claim 1, further comprising: a second
insulating layer, disposed on the active layer, and covering a part
of the first insulating layer exposed by the second through holes
to form a plurality of third through holes; and a gate structure,
disposed on the second insulating layer, and extended into the
third through holes.
5. The transistor of claim 1, wherein a material of the gate layer,
the source and the drain comprises a metal material.
6. The transistor of claim 1, wherein a material of the first
insulating layer comprises a metal oxide material.
7. The transistor of claim 1, wherein a material of the active
layer comprises a metal oxide semiconductor material or an organic
semiconductor material.
8. The transistor of claim 1, wherein a diameter of each of the
second through holes is substantially equal to an inner diameter of
the corresponding recess.
9. A manufacturing method of a transistor, comprising: providing a
substrate; forming an insulating material layer on the substrate;
placing a plurality of blocking balls on a part of a surface of the
insulating material layer; forming a conductive layer on the
surface of the insulating material layer; removing the blocking
balls so that the conductive layer becomes a gate layer having a
plurality of first through holes; removing a part of the insulating
material layer exposed by the first through holes so that the
insulating material layer has recesses communicating with the first
through holes, respectively; forming a first insulating layer, and
causing the first insulating layer to cover the gate layer and to
be formed in the recesses; forming an active layer above the gate
layer, wherein the active layer has a plurality of second through
holes communicating with the first through holes, respectively, and
the first insulating layer separates the gate layer and the active
layer; and forming a source and a drain on a part and another part
of the active layer, respectively.
10. The manufacturing method of the transistor of claim 9, wherein
the step of removing the part of the insulating material layer
exposed by the first through holes comprises etching the part of
the insulating material layer exposed by the first through holes by
using the gate layer as an etching mask layer.
11. The manufacturing method of the transistor of claim 9, wherein
the step of forming the active layer on the gate layer comprises
naturally forming the active layer on the part of the first
insulating layer covered on the gate layer, and the active layer
naturally forms the second through holes.
12. The manufacturing method of the transistor of claim 9, further
comprising: forming a second insulating layer, wherein the second
insulating layer is disposed on the active layer, and covers a part
of the first insulating layer exposed by the second through holes
to form a plurality of third through holes; and forming a gate
structure, wherein the gate structure is located on a part of the
second insulating layer and extended into the third through
holes.
13. The manufacturing method of the transistor of claim 9, wherein
a material of the insulating material layer comprises an organic
dielectric material.
14. The manufacturing method of the transistor of claim 9, wherein
a material of the blocking balls comprises an organic material.
15. The manufacturing method of the transistor of claim 9, wherein
a material of the gate layer, the source and the drain comprises a
metal material.
16. The manufacturing method of the transistor of claim 9, wherein
a material of the first insulating layer comprises a metal oxide
material.
17. The manufacturing method of the transistor of claim 9, wherein
a material of the active layer comprises a metal oxide
semiconductor material or an organic semiconductor material.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority benefit of Taiwan
application serial no. 103129352, filed on Aug. 26, 2014. The
entirety of the above-mentioned patent application is hereby
incorporated by reference herein and made a part of this
specification.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to an electronic device and a
manufacturing method thereof, and more particularly, relates to a
transistor and a manufacturing method thereof.
[0004] 2. Description of Related Art
[0005] Various semiconductor materials are adapted to be used as
sensing elements because the semiconductor materials have favorable
sensitivity to environment variation such as gas, liquid or
temperature. Also, a smart detector may be made of the
semiconductor materials in combination with a microprocessor, so as
to provide great value in use for either general household or
factory environments.
[0006] In order to achieve more preferable sensitivity and enhance
speed of sensing reaction, it is one direct and effective choice as
to increase a surface area of reaction. To achieve aforesaid
purpose, a method in which a porous structure is manufactured on a
semiconductor device is generally used. For now, transistors with
the porous structure are usually manufactured by a photolithography
process. However, the photolithography process has high production
costs and is time-consuming, and multiple processes are required
before deposition of multi-layer structure can be completed. On the
other hand, it is also quite difficult to define the structure
after film formation of a metal oxide is completed.
SUMMARY OF THE INVENTION
[0007] The invention provides a transistor having an active layer
that is porous.
[0008] The invention provides a manufacturing method of a
transistor, which is capable of manufacturing a transistor having
an active layer that is porous by using a simple process with low
costs.
[0009] A transistor according to an embodiment of the invention
includes a substrate, a gate layer, a first insulating layer, an
active layer, a source and a drain. The gate layer is disposed on
the substrate, and has a plurality of first through holes. The
first insulating layer covers the gate layer and a part of the
substrate exposed by the first through holes, and forms a plurality
of recesses respectively corresponding to the first through holes.
The active layer is disposed on the first insulating layer, and has
a plurality of second through holes. The second through holes
communicate with the recesses, respectively. The source is disposed
on a part of the active layer. The drain is disposed on another
part of the active layer.
[0010] In an embodiment of the invention, the transistor further
includes an insulating material layer disposed on the substrate and
located between the gate layer and the substrate. The insulating
material layer has a plurality of pores communicating with the
first through holes, respectively.
[0011] In an embodiment of the invention, the transistor further
includes a second insulating layer and a gate structure. The second
insulating layer is disposed on the active layer, and covers a part
of the first insulating layer exposed by the second through holes
to form a plurality of third through holes. The gate structure is
disposed on the second insulating layer, and extended into the
third through holes.
[0012] In an embodiment of the invention, a diameter of each of the
second through holes is substantially equal to an inner diameter of
the corresponding recess.
[0013] A manufacturing method of a transistor according to an
embodiment of the invention includes the followings. A substrate is
provided. An insulating material layer is formed on the substrate.
A plurality of blocking balls is placed on a part of a surface of
the insulating material layer. A conductive layer is formed on the
surface of the insulating material layer. The blocking balls are
removed so that the conductive layer becomes a gate layer having a
plurality of first through holes. A part of the insulating material
layer exposed by the first through holes is removed so that the
insulating material layer has recesses communicating with the first
through holes, respectively. A first insulating layer is formed and
the first insulating layer is caused to cover the gate layer and to
be formed in the recesses. An active layer is formed on the gate
layer. The active layer has a plurality of second through holes
communicating with the first through holes, respectively, and the
first insulating layer separates the gate layer and the active
layer. A source and a drain are formed on a part and another part
of the active layer, respectively.
[0014] In an embodiment of the invention, the step of removing the
part of the insulating material layer exposed by the first through
holes includes: etching the part of the insulating material layer
exposed by the first through holes by using the gate layer as an
etching mask layer.
[0015] In an embodiment of the invention, the step of forming the
active layer on the gate layer includes: naturally forming the
active layer on the part of the first insulating layer covered on
the gate layer, and the active layer naturally forms the second
through holes.
[0016] In an embodiment of the invention, the manufacturing method
of the transistor further includes the followings. A second
insulating layer is formed. The second insulating layer is disposed
on the active layer, and covers a part of the first insulating
layer exposed by the second through holes to form a plurality of
third through holes. A gate structure is formed. The gate structure
is located on a part of the second insulation layer, and extended
into the third through hole to form a gate protrusion portion.
[0017] In an embodiment of the invention, a material of the
insulating material layer includes an organic dielectric
material.
[0018] In an embodiment of the invention, a material of the
blocking balls includes an organic material.
[0019] In an embodiment of the invention, a material of the gate
layer, the source and the drain includes a metal material.
[0020] In an embodiment of the invention, a material of the first
insulating layer includes a metal oxide material.
[0021] In an embodiment of the invention, a material of the active
layer includes a metal oxide semiconductor material or an organic
semiconductor material.
[0022] Based on above, in the transistor according to the
embodiments of the invention, by using the porous structure formed
by the recesses and the second through holes communicating each
other, the active layer of the transistor is capable of including a
porous structure. Accordingly, the transistor may be developed to
be a sensing element including the active layer having greater
contact area with the outside in order to increase the sensing
sensitivity of the sensing element, or developed to be the fin
field effect transistor having a greater channel width between the
source and the drain. Furthermore, in the manufacturing method
according to the embodiments of the invention, aforesaid porous
structure may be manufactured in low costs and simple process to
provide a potential commercial value through the process step using
the blocking balls and the conductive layer.
[0023] To make the above features and advantages of the disclosure
more comprehensible, several embodiments accompanied with drawings
are described in detail as follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The accompanying drawings are included to provide a further
understanding of the invention, and are incorporated in and
constitute a part of this specification. The drawings illustrate
embodiments of the invention and, together with the description,
serve to explain the principles of the invention.
[0025] FIG. 1A illustrates a three dimensional view of a transistor
according to an embodiment of the invention.
[0026] FIG. 1B illustrates a cross-sectional view of the transistor
in the embodiment of FIG. 1A.
[0027] FIG. 1C illustrates a three dimensional view of a transistor
according to yet another embodiment of the invention.
[0028] FIG. 1D illustrates a three dimensional view of a section of
the transistor of FIG. 1C cut along line I-I.
[0029] FIG. 2A to FIG. 2G are cross-sectional schematic diagrams
illustrating process of a manufacturing method of a transistor
according to another embodiment of the invention.
DESCRIPTION OF THE EMBODIMENTS
[0030] Reference will now be made in detail to the present
preferred embodiments of the invention, examples of which are
illustrated in the accompanying drawings. Wherever possible, the
same reference numbers are used in the drawings and the description
to refer to the same or like parts.
[0031] FIG. 1A illustrates a three dimensional view of a transistor
according to an embodiment of the invention. FIG. 1B illustrates a
cross-sectional view of the transistor in the embodiment of FIG.
1A. Referring to FIG. 1A and FIG. 1B, a transistor 100 of the
present embodiment includes a substrate 110, a gate layer 120, a
first insulating layer 130, an active layer 140, a source 150 and a
drain 160. The substrate 110 can be an insulating substrate, a
conductive substrate or a semiconductor substrate, and a material
of the substrate 110 can be a glass, a silicon, a metal or any
combination thereof. The gate layer 120 is disposed on the
substrate 110, and has a plurality of first through holes 122. In
the present embodiment, a material of the gate layer 120 can be a
metal material such as aluminum. In the present embodiment, the
transistor 100 further includes an insulating material layer 170
disposed on the substrate 110 and located between the gate layer
120 and the substrate 110. The insulating material layer 170 has a
plurality of pores 172 communicating with the first through holes
122, respectively. A material of the insulating material layer 170
includes an organic dielectric material, such as polyvinyl
pyrrolidone (PVP).
[0032] The first insulating layer 130 covers the gate layer 120 and
a part of the substrate 110 exposed by the first through holes 122,
and forms a plurality of recesses 132 respectively corresponding to
the first through holes 122. Because each of the pores 172
communicates with corresponding one of the first through holes 122
of the gate layer 120, the first insulating layer 130 is capable of
covering the part of the substrate 110 exposed by the each of the
first through holes 122 and the pores 172. A material of the first
insulating layer 130 includes a metal oxide material, such as
aluminum oxide (Al.sub.2O.sub.3).
[0033] The active layer 140 is disposed on the first insulating
layer 130, and has a plurality of second through holes 142. The
second through holes 142 communicate with the recesses 132
respectively, and a diameter of each of the second through holes
142 is substantially equal to an inner diameter of the
corresponding recess 132. A material of the active layer 140
includes a metal oxide semiconductor material such as indium
gallium zinc oxide (IGZO) or zince oxide (ZnO), or an organic
semiconductor material such as poly(3-hexylthiophene-2,5-diyl)
(P3HT).
[0034] The transistor 100 further includes the source 150 and the
drain 160. The source 150 is disposed on a part of the active layer
140, and the drain 160 is disposed on another part of the active
layer 140. In the present embodiment, the source 150 and the drain
160 are separately disposed on the active layer 140. A material of
the source 150 and the drain 160 includes a metal material such as
aluminum.
[0035] In the present embodiment, the pores 172, the first through
holes 122, the recesses 132 and the second through holes 142 on the
transistor 100 are corresponding and communicating with each other
to form the transistor 100 with a porous structure as shown in FIG.
1A and FIG. 1B. Accordingly, this allows the active layer 140 of
the transistor 100 of the present embodiment to have a greater
contact area with the outside to serve as a sensing element with
favorable sensibility (e.g., a sensing element for gas, liquid or
temperature). In addition, the structure of the transistor 100 of
the present embodiment can also facilitate in subsequent processes
for material deposition.
[0036] In another embodiment of the invention, the insulating
material layer 170 may be omitted if the material of the substrate
110 is an insulating material with the rest in the structure
identical to those in the embodiment of FIG. 1A and FIG. 1B, so as
to accomplish an effect of structure simplification.
[0037] In yet another embodiment of the invention, aforesaid porous
structure may also be designed as a structure having strip trenches
with a section thereof as illustrated in FIG. 1B, so as to increase
the contact area of the active layer 140 with the outside.
[0038] FIG. 1C illustrates a three dimensional view of a transistor
according to yet another embodiment of the invention. FIG. 1D
illustrates a three dimensional view of a section of the transistor
of FIG. 1C cut along line I-I. Referring to FIG. 1C and FIG. 1D
together. A transistor 200 of the present embodiment is an
extension application of the embodiment described in FIG. 1A and
FIG. 1B. The transistor 200 of the present embodiment is similar to
the transistor 100 of FIG. 1A and FIG. 1B, a major difference
between the two is that the transistor 200 further includes a
second insulating layer 180 and a gate structure 190. In other
words, in the present embodiment, the structure of the transistor
100 of the embodiment of FIG. 1A and FIG. 1B is utilized together
with the second insulating layer 180 and the gate structure 190
further formed thereon. The second insulating layer 180 is disposed
on the active layer 140, and covers a part of the first insulating
layer 130 exposed by the second through holes 142 to form through
holes 182. The gate structure 190 is disposed on the second
insulating layer 180, and extended into the third through holes 182
to form a plurality of gate protrusion portions 192. In the present
embodiment, the second insulating layer 180 covers a part of the
source 150 and a part of the drain 160. Nevertheless, in other
embodiments, it is also possible that the second insulating layer
180 does not cover the source 150 and the drain 160. However, the
invention is not limited thereto. A material of the second
insulating layer 180 includes a metal oxide material, such as
aluminum oxide (Al.sub.2O.sub.3). A material of the gate structure
190 can be a metal material such as aluminum.
[0039] In the foregoing embodiment, a porous structure of the
transistor 200 is utilized to dispose the gate structure 190 having
the gate protrusion portions 192 on the active layer 140 with the
porous structure, such that the transistor 200 of the present
embodiment forms a structure of a fin field effect transistor which
has a more preferable capability in gate-to-channel control in
comparison with structures of traditional transistors, so as to
improve an electrical quality of the transistor 200.
[0040] FIG. 2A to FIG. 2G are cross-sectional schematic diagrams
illustrating process of a manufacturing method of a transistor
according to another embodiment of the invention. Referring to FIG.
2A to FIG. 2G, the manufacturing method of the transistor of the
present embodiment can be used to manufacture the transistor 100 of
FIG. 1A and FIG. 1B, and includes the following steps. First, as
illustrated in FIG. 2A, a substrate 110 is provided. Then, an
insulating material layer 170a is formed on the substrate 110. A
material of the insulating material layer 170a includes an organic
dielectric material, such as polyvinyl pyrrolidone (PVP).
Subsequently, as illustrated in FIG. 2B, a plurality of blocking
balls B are placed on a surface of a part of the insulating
material layer 170a, and configured to prevent the part of the
insulating material layer 170a from contacting materials formed in
the subsequent processes. A material of the blocking balls B
includes an organic material such as polystyrene (PS).
[0041] Next, as illustrated in FIG. 2C, a conductive layer 120a is
formed on the surface of the insulating material layer 170a. A
material of the conductive layer 120a can be a metal material such
as aluminum. Thereafter, as illustrated in FIG. 2D, the blocking
balls B are removed, so that the conductive layer 120a becomes a
gate layer 120 having a plurality of first through holes 122. In
this case, a part of the insulating material layer 170a is exposed
by the first through holes 122.
[0042] Subsequently, as illustrated in FIG. 2E, the part of the
insulating material layer 170a exposed by the first through holes
122 is removed, so that the insulating material layer 170a becomes
an insulating material layer 170 having recesses 132' communicating
with the first through holes 122, respectively. A method of
removing the part of the insulating material layer 170a exposed by
the first through holes 122 includes the following. The part of the
insulating material layer 170a exposed by the first through holes
122 is etched by using the gate layer 120 as an etching mask layer.
As a result, pores 172 are formed, and the pores 172 communicate
with the first through holes 122, respectively.
[0043] Referring to FIG. 2F which follows after the step of FIG.
2E, a first insulating layer 130 is formed, and the first
insulating layer 130 is made to cover the gate layer 120 and to be
formed in the recesses 132', so as to form recesses 132.
Subsequently, as illustrated in FIG. 2G, an active layer 140 is
formed above the gate layer 120. While forming the active layer
140, the active layer 140 is naturally formed on the part of the
first insulating layer 130 covered on the gate layer 120. The
active layer 140 naturally forms aforesaid second through holes
142, and the second through holes 142 communicate with the first
through holes 122, respectively. A method of forming the active
layer 140 includes an oblique evaporation or a vertical
evaporation. It should be noted that, in the manufacturing method
of the transistor of the present embodiment, the recesses 132 of
the first insulating layer 130 have a high aspect ratio, i.e. the
ratio of the height to the width. Therefore, during the
evaporation, the active layer can be selectively formed in relative
to the first insulating layer 130 having the recesses 132, such
that the active layer 140 can be naturally formed on the part of
the first insulating layer 130 covered on the gate layer 120.
[0044] Then, as illustrated in FIG. 1B, a source 150 and a drain
160 are formed on a part and another part of the active layer 140,
respectively, so as to form the transistor 100. The source 150 and
the drain 160 may be formed in the same step, or formed in
different steps, respectively.
[0045] In the manufacturing method of the transistor according to
the present embodiment, the blocking balls B are utilized to
manufacture the first through holes 122 of the conductive layer
120a, and then the gate layer 120 formed by the conductive layer
120a is utilized to serve as the etching mask layer, so that the
transistor with the porous structure can be manufactured
accordingly. In the present embodiment, the recesses 132 of the
first insulating layer 130 with the surface of the porous structure
have a large aspect ratio. This method is advantageous in low costs
and simply manufacturing process without repeatedly performing the
step for the photolithography process, and adapted to developments
for the sensing element (e.g., the sensing element for gas, liquid
or temperature) with favorable sensibility and reasonable
price.
[0046] In yet another embodiment of the invention, a manufacturing
method of a transistor may be used to manufacture the transistor
200 of FIG. 1C and FIG. 1D. This method can be used to further
manufacture the transistor 100 manufactured based on the
manufacturing method illustrated in FIG. 2A to FIG. 2G.
Hereinafter, the manufacturing method described in the embodiment
of FIG. 2A to FIG. 2G is not repeated hereinafter.
[0047] In the present embodiment, a fin field effect transistor
(i.e., the transistor 200 of FIGS. 1C and 1D) can be further
manufactured by utilizing the transistor 100 of FIG. 1A and FIG.
1B, and the manufacturing method includes the following steps. A
second insulating layer 180 is formed on the manufactured
transistor 100, and covers the active layer 140 and the drain 150
and the drain 160. The second insulating layer 180 also covers a
part of the first insulating layer 130 exposed by the second
through holes 142 to form a third through holes 182. A material of
the second insulating layer 180 includes a metal oxide material,
such as aluminum oxide (Al.sub.2O.sub.3). It should be noted that,
in another embodiment, the second insulating layer can cover the
active layer 140 without covering the source 150 and the drain 160.
However, the invention is not limited thereto.
[0048] Subsequently, the gate structure 190 is formed on the second
insulating layer 180, and extended into the third through holes 182
to form a plurality of gate protrusion portions 192. A material of
the gate structure 190 can be a metal material such as
aluminum.
[0049] In the foregoing embodiment, the transistor 200 manufactured
by utilizing the structure of FIG. 1 A and FIG. 1B has a structure
of the fin field effect transistor. This process method may be used
to manufacture the transistor 200, which has a more preferable
capability in gate-to-channel control in comparison with structures
of traditional transistors, by using a simpler process, so as to
improve the electrical quality of the transistor 200.
[0050] In summary, the transistor according to the embodiment of
the present embodiment includes the porous structure having large
aspect ratio, such that the active layer also includes the porous
structure. Accordingly, the transistor may be developed to be a
transistor including the active layer having greater contact area
with the outside in order to increase the sensing sensitivity of
the sensing element, or developed to be the fin field effect
transistor having a greater channel width between the source and
the drain.
[0051] In terms of applications for the transistor structure, the
fin field effect transistor according to the embodiments of the
invention and the manufacturing method thereof includes a simpler
manufacturing process and more preferable capability in
gate-to-channel control in comparison with structures of
traditional transistor, such that the electrical quality of the
transistor can be improved.
[0052] Furthermore, when the transistor with the porous structure
having large aspect ratio is manufactured by using the
manufacturing method of the transistor structure according to
embodiment of the invention, it is advantageous in low costs and
simple process through the process step using the blocking balls
and the conductive layer because it is not required to repeatedly
perform the step for photolithography process, and is adapted to
developments for the sensing element with favorable sensibility and
potential commercial value.
[0053] It will be apparent to those skilled in the art that various
modifications and variations can be made to the structure of the
present invention without departing from the scope or spirit of the
invention. In view of the foregoing, it is intended that the
present invention cover modifications and variations of this
invention provided they fall within the scope of the following
claims and their equivalents.
* * * * *